Brain Temperature Measurement in Rats: A Comparison of Microwave and Ambient Temperature Exposures

摘要

The brain and core temperatures of rats and rat carcasses exposed to microwave radiation (2450 MHz) or elevated air temperatures were measured in two studies. In general, no substantial evidence for temperature differentials, or hot spots, in the brain of these animals was found. In the first study, rats and rat carcasses were exposed to a series of power densities or a series of ambient air temperatures. The temperature of the core and eight brain regions was measured before and after exposure. No temperature differences between brain regions were found. However, a highly significant correlation between brain and core temperatures was found and this correlation was the same for both microwave and ambient air heating. In the second study, rats and rat carcasses were exposed to either 30 mW/ sq cm or 40 deg C while core and three regional brain temperatures were recorded continuously. For analysis, the 30 minute exposure period was broken into seven intervals and the change in temperature during each period was analyzed. In the live animal, only the cortex showed significantly different heating rates between the air heating and microwave heating; however, this difference disappeared after the initial five minutes of exposure. In the rat carcass, both the hypothalamus and the cortex initially showed significant differences in rate of temperature change but these differences also disappeared after 10 minute of exposure. (Copyright (c) 1986 Alan R. Liss, Inc.)